Finally, putting everything together—using both the answer span scoring technique of [1]} and incorporating retriever scores—we observe statistically significant gains across all retrieval conditions, as can be seen in the “GAR*” vs. “repl” columns across all rows.
Compared to the best replicated results, we obtained an improvement of approximately three points in end-to-end QA effectiveness compared to the best answer extraction approach described in [2]}.
Note that we were able to obtain these improvements using exactly the model checkpoints provided in the DPR repo—we have simply added two relatively simple tricks to improve scoring and evidence combination.
